Matrix-free desorption ionization mass spectrometry using tailored morphology layer devices

ABSTRACT

There is disclosed an apparatus for providing an ionized analyte for mass analysis by photon desorption comprising at least one layer for contacting an analyte, and a substrate on which said layer is deposited. Upon irradiation of said apparatus, said analyte desorbs and ionizes for analysis by mass spectrometry. The layer or layers of said apparatus comprise a continuous film, a discontinuous film or any combinations thereof.

[0001] This application claims priority from U.S. ProvisionalApplication No. 60/290,876, filed May 14, 2001, and is a continuation inpart application of U.S. application Ser. No. 09/580,105, filed May 30,2000. This application also claims priority from U.S. patent applicationSer. No. 10/104,749, filed Mar. 22, 2002, which is a continuation ofU.S. patent application Ser. No. 09/580,105, filed May 30, 2000.Priority is also claimed from U.S. application Ser. No. 09/836,449,filed Apr. 17, 2001, which is a continuation in part of U.S. patentapplication Ser. No. 09/739,940, filed Dec. 19, 2000, which is acontinuation in part of U.S. patent application Ser. No. 09/580,105,filed May 30, 2000.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to tailored-morphology materialsystems and their use in molecular mass analysis by electromagneticenergy desorption-ionization mass spectrometry. Areas of interest forthis technology include, but are not limited to, chemical research andmanufacturing, pharmaceutical research and manufacturing, bio-medicalresearch and screening, head-space and environmental monitoring, andother applications involving molecular analysis.

[0004] 2. Description of the Prior Art

[0005] Light desorption-ionization mass spectrometry is a very commonand powerful technique for mass analysis of molecules. It is a techniquewhich can be broadened to include the whole spectrum of electromagneticenergy for the desorption-ionization step. However, with recent demandsin throughput and small molecule screening, the most popular and widelyused laser-based technique, known as MALDI (matrix-assisted laserdesorption-ionization), has limitations. MALDI was developed in themid-eighties and is still being refined today for the analysis of a widerange of compounds with emphasis on proteins, peptides and othermolecules in the range of 500-200,000 amu. In MALDI, the analyte (themolecules or compounds to be analyzed) is mixed in with an organic UVabsorbent “matrix”. This matrix provides a “soft” method of desorbinglarge molecules by allowing excess energy in the analyte to betransferred to the matrix molecules during the desorption process. Thematrix also provides an environment suitable for the protonation of theanalyte molecules, giving them a single, positively charged state.However, for small molecules (approximately 500 amu and below, such asdrug molecules), the matrix molecules themselves provide background inthe signal and complicate spectrum analysis. Furthermore, with moderndemands in automation, throughput and reproducibility, the addition ofthe matrix to the analyte and its preparation become issues particularlyin the case of throughput. These limitations were recognized during theonset of MALDI, leading to the study of non-matrix methods.

[0006] The first studies in matrix-less light desorption from a surfaceused metals and glasses as a media to immobilize the analyte molecules.These materials had non-textured morphologies, i.e., essentially theywere non-porous and had a flat (continuous) surface. In a study usingthis approach, two incident light beams were used, one to desorb and oneto ionize the molecules. Zhan, Q. et al., Amer. Soc. Mass Spectrom. 8,525-531 (1997). This approach is termed two-photon ionization. Othersimilar methods used ion beams and thermal sources for these tasks.Problems with all these matrix-less light desorption techniques reportedin the literature include a high degree of molecular fragmentation and avery limited mass range. These studies, and recent comments, maintainthat smooth (non-porous) surfaces do not work effectively formatrix-less laser mass desorption. (See for example, Wei, J., et al.,Nature. 399, 243-246 (1999). A recent report supports the understandingthat smooth surfaces do not function effectively for matrix-less lasermass desorption. Kruse, R., et al., Anal. Chem. 73, 3639-3645, 2001.

[0007] It has been shown that matrix-less laser mass desoroption couldbe effective if done on a textured surface created with the use ofelectrochemically etched porous silicon. Wei, J., et al., Nature. 399,243-246 (1999). With this material as a substrate for laser desorptionionization, significant improvement in non-matrix techniques formolecular analysis has been reported. Also, it was reported thatelectrochemically etched porous silicon provided mass detection in therange of 0-8000 amu with little fragmentation and little low mass noise.However, other results using this material raised concerns about the lowmass collection of hydrocarbons and other contaminants leading to“dirty” low mass signals. Shen, Z., et al., Anal. Chem. 73, 612-619(2001). The use of HOME-HF electrochemically etched Si, GaAs and GaN,which requires metallic patterning and a wet etching step leading to aporous microstructure, has also been reported for matrix-less laser massdesorption. Kruse, R., et al., Anal. Chem. 73, 3639-3645, 2001.

[0008] Further limitations of the electrochemically etched materials aretheir limited useful lifetimes for mass desorption-ionizationapplications (<3 weeks) which occur for these materials because ofetchants trapped in the material during its manufacturing process. Theprocessing of these etching approaches involves the galvanic etching ofa crystal conductive substrate in a hydrofluoric acid based solution.Although the fundamental theory of the mechanism ofdesorption-ionization of molecules using these techniques is currentlyunder investigation, research groups using these materials reported theimportance of the porous structure to the success of massdesoprtion-ionization and reported that solid, smooth (i.e.,non-textured) silicon and silicon dioxide coated silicon did notgenerate ion signals; i.e., were not useful for light desorbed massspectroscopy. In other work, liquid matrix materials combined with UVlight adsorbing particles have been used in recent laserdesorbtion/ionization experiments as an alternative to traditional MALDImatrix materials. Dale et al, Anal Chem, 68, 3321-3329 (1996) used aglycerol/graphite slurry to desorb detect proteins and peptides. Thismethodology proved less efficient in ionization than traditional MALDIand provided a very noisy spectrum from the glycerol contamination.

[0009] The use of a new material, deposited column/void network silicon,for laser desorption-ionization has eliminated several disadvantagesassociated with electrochemically etched material approaches. Cuiffi,J., et al., Anal. Chem. 73, 1293-1295 (2001). This reported technique ofusing deposited column/void network materials for massdesorption-ionization produced similar mass ranges and sensitivity toelectrochemically etched material, but the film itself did not degradeover time. Furthermore the manufacturability of a deposited film systemoffers several advantages in cost, production throughput, contaminationcontrol, uniformity, and signal reproducibility. This deposited materialalso offers the further unique feature of having the capability to bedeposited on a number of inexpensive substrates, includingbio-degradable materials, plastics, and glass. On the other hand,electrochemically etched material always must be on a conductingsubstrate. In addition, Cuiffi et al. reported, for the first time, thatsolid (continuous) films of crystalline silicon and thermal silicondioxide coated crystal silicon did give effective massdesorption-ionization spectroscopy signals. Cuiffi, J., et al., Anal.Chem. 73, 1293-1295 (2001).

[0010] The material systems of the present invention consist of one ormore deposited film layers and a substrate on which they are deposited.The material system could also be grown (e.g., Si, SiGe alloy, Ge wafermaterials) or casted (Si, SiGe, Ge sheet materials) and also function asthe substrate. Unlike the previously reported techniques, our depositedmaterial systems offer the flexibility of a number of deposition methodsand encompass a broad range of material and morphological choices. Thesematerial systems can be uniquely tailored for mass spectrometryapplications through choice of the substrate, deposition techniques andmaterials, deposition parameters and pre- or post deposition physicaland chemical modification, which are unavailable in the techniques ofelectrochemically etched porous silicon whether used with one ortwo-photon ionization. Specifically, the substrate materials availablewith our technique are chosen from a group consisting of polymers,plastics, bio-degradable materials, semiconductors, metals, ceramics,insulators, glasses or combinations thereof. Electrochemically orHOME-HF etched porous materials require a conducting semiconductorsubstrate, and are fundamentally based on a subtractive electriccurrent-driven etching process.

[0011] The materials of the present invention can be deposited. This canbe done by one or a combination of the additive process comprisingphysical vapor deposition, chemical vapor deposition, molecular beamepitaxy, plasma assisted physical vapor deposition, plasma enhancedchemical vapor deposition, sol-gel, molecular self-assembly,electroplating, tape casting, spin casting, casting, liquid deposition,or assembly from liquid chemical precursors. The morphology of thesematerials, which is determined by the production technique andparameters, are application-specific and can range from a continuous(void free) solid with no surface texturing to high surface area tovolume ratio (i.e., the deposited column-void nanotextured siliconfilm), or any intermediate morphologies.

[0012] The material systems of the present invention can also be alteredby pre or post deposition physical or chemical modifications, whichaffect the morphology, surface chemistries and bulk material chemistriesof the films.

[0013] Given these advantages, our material systems are easilyintegrated, when compared to other matrix-less lightdesorption/ionization techniques, with microelectronics, micro-fluidicsand other micro and nanofabricated sensing devices.

[0014] Matrix free desorption/ionization mass spectrometry availableusing the tailorable morphology of our materials, has a variety ofapplications. The flexible nature of the substrate material composition,film composition, or both, permitted in our approach allows thistechnology to be used in atmospheric and reduced pressure desorption andionization systems as a disposable consumable or reusable target. Thecomposition and methods of production utilized in this technique allowfor easy integration with microfabrication processes and microelectronicdevices, such as microfluidics, microarrays, CMOS technology and thinfilm transistors. The matrix less desorption and ionization makesautomated, high throughput sample analysis an attractive use of thistechnique.

[0015] The present invention presents a variety of structures thatfurther expand the possibilities of molecular detection using lightdesorption-ionization, by providing low-cost, easily manufactured,tailorable material systems and techniques.

SUMMARY OF THE INVENTION

[0016] The present invention is directed to a class of layeredstructures comprising one or more layers, with tailoredapplication-specific morphology, for use in light desorption-ionizationmass spectrometry. This class of structures holds analytes and allowsthem to be desorbed and ionized in the presence of a light source forsubsequent mass analysis. Analytes are preferably in an amount less thanone millimole. Analyte is selected from the group consisting of organicchemical compositions, inorganic chemical compositions, biochemicalcompositions, cells, micro-organisms, peptides, polypeptides, proteins,lipids, carbohydrates, drug candidate molecules, drug molecules, drugmetabolites, combinatorial chemistry products, nucleic acids, and anycombinations thereof.

[0017] In order to perform [these two] the functions of desorption andionization, the film structure and substrate of this invention must (1)effectively couple and absorb the incident electromagnetic energy (e.g.,light), (2) transfer the energy from the incident energy into theanalyte for desorption/ionization, and (3) provide the necessary surfaceand surroundings for the analytes to be desorbed and ionized. Thestructures of this invention may also be patterned or textured for tasksincluding increasing the surface area, enhancing ionization, enhancingoptical absorption, and localizing the analyte. Also, chemical additivesto the deposited films or analyte solution may also be used to enhanceionization and analyte detection. Finally, these material systems can beeasily integrated with macro-scale and micro-scale devices. Theseaspects are explained and further detailed below. The class ofstructures of the present invention encompasses devices with one or moredeposited films and a substrate to which they are adhered. The class ofstructures of this invention also encompasses structures with one ormore layers from grown or caste materials.

[0018] Each layer in the device, including the substrate may perform oneor more tasks. Two necessary tasks are the absorption of the light (doneby the “absorption layer”) and holding of the analyte (done by the“immobilization layer”). Other tasks may include enhancing opticalcoupling of the light into the absorber via increasing optical pathlength and/or optical impedance matching, enhancing thermal energytransfer into the analyte via high thermal conductivity, controllingdrop drying and crystallization and providing a source of ionizing orionizing enhancing reagents. A layer may also be present to apply a biasto the analyte-bearing layer during the light impingement step.

[0019] The present invention discloses an apparatus for providing anionized analyte for mass analysis by light desorption mass spectrometrycomprising at least one layer for contacting an analyte, and a substrateon which said layer is deposited, wherein said analyte upon irradiationof said apparatus with a light source desorbs and ionizes for analysisby mass spectrometry. The substrate is selected from the groupconsisting of semiconductors, glasses, plastics, polymers, biodegradableor biocompatible materials, metals, ceramics, insulators, organicmaterials, and any combinations thereof. At least one layer is selectedfrom the group consisting of metals, semiconductors, insulators,ceramics, polymers, organic materials, inorganic materials, and anycombinations thereof. At least one layer may be a continuous(non-textured) film, a textured (columnar or columnar-void) film, or anycombinations thereof, and is deposited by physical vapor deposition,chemical vapor deposition, liquid deposition, molecular beam epitaxy,plasma assisted chemical vapor deposition, sol-gels, nebulization,electroplating, tape casting, spin coating, self-assembly, assembly fromliquid chemical precursors, printing, and any combinations thereof.

[0020] The present invention also discloses a method for providing anionized analyte for analysis of mass comprising providing an apparatuscomprising at least one layer for contacting an analyte wherein saidlayer is deposited on a substrate, contacting an amount of an analytecontaining entities such as molecules whose mass or masses are to bedetermined with said deposited layer, and irradiating said apparatus todesorb and ionize said analyte. Also, the present invention discloses amethod for determining a physical property of an analyte componentcomprising providing an apparatus comprising at least one layer forcontacting an analyte and a substrate on which said layer is deposited;positioning an amount of an analyte on the layer used for contacting ananalyte of said apparatus; irradiating said apparatus having saidcontacted analyte; desorbing and ionizing at least one component of saidanalyte; and analyzing said ionized analyte component for a physicalproperty, preferably mass to charge ratio of the ionized analylte.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021]FIG. 1 is a schematic representation of the difference betweenMALDI (top) and the method of the present invention (bottom).

[0022]FIG. 2 is a mass spectrum obtained using a silicon dioxide layeron top of silicon.

[0023]FIG. 3 is a mass spectrum obtained using a deposited germaniumthin film.

[0024]FIG. 4 is a mass spectrum obtained using a high surface to volumesilicon material.

[0025]FIGS. 5a-f show various material system embodiments of the presentinvention.

[0026]FIG. 6 Transmission and reflectance spectra of the Halogenatedacidic polymer—carbon black composite film. Reflectance is with respectto barium sulfate.

[0027]FIG. 7. Desorption ionization mass spectrum taken from the surfaceof the Carbon black—Halogenated acidic polymer film.

DETAILED DESCRIPTION OF THE INVENTION

[0028] Referring now to FIG. 1, there is shown a schematicrepresentation of the MALDI and the method of the present invention.Ultra-violet light (337 nm) 1 impinges matrix 2 to provide sample andmatrix ions and neutrals 3 to reach detector 4.

[0029] Referring now to FIG. 5 which shows devices of various materials,FIG. 5a shows a device having a high surface area to volume ratio filmor layer of columnar silicon 11 on a plastic substrate 10. The functionsof the columnar silicon layer 11 are absorption, optical coupling, andimmobilization. Advantages of this device include, but are not limitedto, one-step production, inexpensive substrate material, and highmolecular immobilization.

[0030]FIG. 5b shows a device having a layer of silicon dioxide 15 on alayer of amorphous silicon 12, on a layer of metal 13, on a glasssubstrate 14. The function of the amorphous silicon layer 12 is lightabsorption. The metal 13 and silicon dioxide 15 provide opticalcoupling; also, the silicon dioxide layer 15 provides immobilization.Advantages of this device are that it is reusable and provides littlelow mass noise.

[0031]FIG. 5c shows a device having a layer of silicon dioxide 17 on asubstrate of crystal silicon 16. The function of the crystal siliconsubstrate 16 is light absorption. The functions of the silicon dioxidelayer 17 are optical coupling and immobilization.

[0032]FIG. 5d shows a device having a layer of amorphous silicon 19 on atextured plastic substrate 18. The functions of the amorphous siliconlayer 19 are light absorption and analyte immobilization. The functionof the textured plastic substrate 18 is optical coupling.

[0033]FIG. 5e shows a device having a layer of amorphous silicon 21 on aglass substrate 20. The functions of the amorphous silicon layer 21 arelight absorption and analyte immobilization. Neither the glass substrate20 nor the amorphous silicon layer 21 provides optical coupling. Theadvantages of this device include, but are not limited to, one-stepproduction of manufacture, and low mass noise.

[0034]FIG. 5f shows a device having a high surface area to volume ratiosilicon dioxide (porous SiO₂) layer 24 on a layer of amorphous silicon23 on a glass substrate 22. The device is preferably illuminated frombelow, i.e., from the glass substrate layer 22. The function of theamorphous silicon layer 23 is light absorption of the back illumination.The function of the porous SiO₂ layer 24 is analyte immobilization. Thefunction of the glass substrate layer 22 is optical coupling. Advantagesof this device include, but are not limited to, elimination of directlight exposure of the anlyte by providing illumination from below, andhigh molecular immobilization.

[0035]FIG. 6 is a graphic representation of transmission and reflectancespectra a halogenated acid polymer—carbon black composite film of thepresent invention. Reflectance is with respect to barium sulfate.Exceptionally low reflectance and almost no transmission indicated thatthe composite film absorbs most of the light impinging on it in thevisible and ultraviolet range.

[0036]FIG. 7 is a graphic representation of a desorption ionization massspectrum taken from the surface of a carbon black—halogenated acidicpolymer film of the invention.

[0037] Absorption Layer

[0038] A necessary role that one or more layers, which may include thesubstrate, must play is the absorption of the incident photons and theconversion of this light into species-desorbing energy. The opticalproperties required by this absorption layer are determined by theelectromagnetic energy (e.g., light) source used. For example, siliconmakes an excellent absorber for an ultra-violet light source such ascommon nitrogen laser (wavelength of 337 nm), but may not workeffectively with an infra-red source (depending on the wavelength)because of its optical bandgap structure. On the other hand, Ge willwork for the shorter infra-red wavelengths. In general this absorberlayer composition is selected to match the wavelength or wavelengths ofthe impinging electromagnetic radiation. Materials that can be used forthis layer, with appropriate optical properties, include conductors,semiconductors, insulators, ceramics, polymers, organic materials,inorganic materials, or composites thereof. Proper choice of this layercan allow the electromagnetic energy source to be a variety ofpossibilities including light emitting diodes or lasers.

[0039] A micro-composite or nano-composite polymer film can also be usedfor this layer, which may include the substrate, in matrix-less photondesorption mass analysis devices or apparatuses. For example, a polymerincluding but not limited to, an acidic halogenated polymer, or mixturesof halogenated polymers, may be added to an inorganic or organicmaterial, or combinations thereof. A preferred composite embodimentcomprises a fluorinated, acidic polymer and carbon black. Compositepolymer films or layers are conveniently prepared by mixing the selectedorganic polymer and inorganic/organic material (i.e., fluorinated acidicpolymer and carbon black) in a suitable solvent; and thereafter forminga composite film from the mixture. The composite film may be formed bymethods known in the art such as molding, casting, spin casting,spraying, and any combinations thereof. An advantage of using compositepolymer films is that desirable properties of materials essential tolaser desorption ionization are consolidated. For example, when afluorinated, acidic polymer/amorphous carbon composite comprising carbonblack particles embedded or suspended in the polymer matrix is used,carbon black particles efficiently absorb the laser energy and convertit to heat while the acidic polymer provides a means of holding thecarbon particles together and can function to mediate proton transfer asa donating medium for the analyte. Modifying the polymer content orpolymer chemistry also offers a means to control the surface energy ofimmobilization layer and therefore modify the adsorption, drying andcrystallization of the analyte.

[0040] Immobilization Layer

[0041] The one or more necessary layers which are in contact with thesample atoms and/or molecules must hold the sample and allow it toeffectively desorb and ionize, enabling it to interact with anyionizing/ionization enhancing agents if necessary. This layer may becomposed of the same or similar material as the light coupling, thermalcoupling, or absorption layer or may differ in both chemical compositionand physical morphology. The morphology of this layer may range fromsolid, flat-surface (non-textured) material to high surface area tovolume ratio very highly nano-textured material. The morphology of thefilm may be used to affect the mechanics and kinetics of analyteapplication, adsorption and concentration, and/or the adsorption andconcentration of the ionizing and ionization enhancement agents. Thisaffects signal properties, including but not limited to, sensitivity andresolution.

[0042] The chemical composition of this layer or layers can also affectsignal response by modifying the interaction of the atomic and/ormolecular species and other compounds with each other and the layer.Chemical composition of this layer may change species adsorption,desorption, ionization, conductivity and molecular affinity of thelayer. The chemical composition of this layer may also affect itsability to be cleansed of noise (non-analyte) molecules during analytepositioning. The bulk and surface chemistries may be specificallytailored, by controlling layer processing (e.g., casting, deposition)chemistry or by post layer processing modification for controlling theaforementioned properties. We have demonstrated that hydrophobic orhydrophilic and acidic or basic surfaces influence analyte desorptionand ionization by modifying analyte, ionizing agent and surfaceinteraction. The reduction of van der Walls and hydrogen bonding viasurface chemistry also may enhance analyte desorption/ionization. Theimmobilization layer or layers that are in contact with the sample atomsand/or molecules may be comprised of conductors, semiconductors,insulators, ceramics, polymers, organic materials, inorganic materials,or composites thereof.

[0043] This layer of the matrix-less devices of the present inventionfor photon desorption mass analysis may be a composite polymercontaining film. The film may be either a micro-composite or anano-composite film. Such composite polymer films include, but are notlimited to, a suitable acidic halogenated polymer, or mixtures of acidichalogenated polymers, and a suitable organic or inorganic material, orcombinations thereof. A preferred composite embodiment comprises acidicfluorinated polymer and the material carbon black.

[0044] Optical Coupling Layer

[0045] Another task that may be performed by one or more layers of thematerial system of this invention is coupling the incident light moreeffectively into the absorption layer. Several techniques can be usedincluding optical impedance matching, anti-reflection coating,increasing the optical path length, and combinations thereof. Materialsthat can be used for this layer, with appropriate properties, includemetals, semiconductors, insulators, ceramics, polymers, organicmaterials, inorganic materials, or composites thereof.

[0046] Substrate

[0047] For the material system of this invention, the substrate may playone or more of the roles mentioned above or simply serve as a supportmedium. The only necessary qualification of the substrate is that itmust be compatible with the processing used to create subsequent layers.Materials that can be used for this layer include metals,semiconductors, insulators, ceramics, polymers, organic materials,inorganic materials, or composites thereof.

[0048] One or more of the different layers of the devices of theinvention may be a conductor capable of being biased during theimpingement of the desorbing light. Such layer biasing may be used toaffect ionization of the analyte.

[0049] Processing Methods

[0050] The layers of these morphology tailored structures can come fromgrown or caste materials. They can be deposited films produced by avariety of methods including but not limited to the following: PVD suchas sputtering, evaporation, and PEPLVD, CVD PECVD, ECR-PECVD, MOCVDelectroplating, so-gel, tape casting, spin coating, nebulization,deposition, self-assembly, casting, liquid deposition, or assembly fromliquid precursors, and any combinations thereof.

[0051] Composite polymer layers or films of the devices or apparatusesof the present invention may be prepared by methods known in the art.For example, organic polymers or polymers are mixed with organic orinorganic material or materials in a suitable solvent. A preferredorganic polymer is a crosslinked halogenated acidic polymer. A preferredinorganic material is carbon black. The mixture is then formed into afilm with removal of the solvent using methods known in the art such asmolding, casting, spin casting, spray, and any combinations thereof.

[0052] Device Structure and Layer Organization

[0053] The layer options and requirements detailed above enable thematerial structures of this invention to be uniquely tailored foroptimal performance based on the analytes, their sample preparation, thetype of electromagnetic energy source used for desorption-ionization,the mass analysis technique and integration techniques. However, severalbasic rules apply to the overall device structure. These rules applywhether the electromagnetic energy enters through the immobilizationlayer holding the analyte (the front) or from the back. First, theimpinging photons must be able to enter the absorber layer or layers ofthe device. Second, the immobilization layer must enable the desorbedanalytes to have access to the mass detector.

[0054] Device Texturing and Patterning

[0055] The texturing of one or more layers in the device of thisinvention can have several effects. Texturing of a reflective layerbehind the absorber (on the opposite side of the device from the lightsource), increases the optical path length and enhances opticalabsorption in thin absorber layers. Texturing of the immobilizationlayer can have various effects depending on the length scale considered.Micro- or nano-scale or both roughness allows more analyte anddesorption-ionization enhancing agents to be present per incidentimpinging photon area. This can increase the sensitivity and longevityof analyte signal. On the nano-scale, the surface roughness will notonly enhance signal sensitivity and longevity by increasing the absoluteamount of analyte present, but may also act to enhance light couplinginto the absorber by optical impedance matching. Texturing can be doneby a variety of manufacturing techniques including pre-fabricated ormolded substrates, physical roughening, laser ablation, lithographicprocesses, etching processes and textured film growth.

[0056] Patterning of one or more of the layers in the device can servemany purposes. The localization of analytes, which is important forautomation and sample delivery purposes, can be done on a macroscopic ormicroscopic scale with wells either pre-formed on the substrate orproduced during subsequent film growth and processing. Furthermore,patterning of the immobilization layer via differences inhydrophobicity, hydrophilicity, chemical affinity, charge and polaritycan localize and preferentially bind desired analytes. Patterning of ametallic grid on the immobilization layer can remove charge buildupduring the desorbtion/ionization process in machines requiring agrounded stage. Finally, with the integration of these devices intomicro-fluidic systems, patterning can be used to define the devicelocation. Patterning can also be done by a variety of manufacturingtechniques including pre-fabricated or molded substrates, physicalscribing, laser ablation and lithographic processes.

[0057] Photon Impingement Protocols

[0058] To extend the temporal duration or amount of analyte signalgeneration, it may be necessary to have the impinging photons execute apattern in each given analyte-containing region. Such patterns wouldallow more analyte to be desorbed and may involve multiple paths acrossa given region. These protocols would be pre-programmed.

[0059] Chemical Additives

[0060] Chemical additives, which are allowed to interact with theanalyte molecules during the desorption-ionization process, can act toenhance analyte detection. In order to increase the proportion ofcharged analyte species to neutrals, the surrounding environment can bemade more acidic or basic. To create a more “soft” ionization processknown molecules can be used with the analyte to act as a cooling mediaby which excess thermal energy may be transferred from the analyteduring desorption. This greatly reduces the fragmentation of largemolecules during mass analysis. Other chemical additives can act tocondition or purify the surrounding media by chelating metal and saltions known to reduce sensitivity and cause adducts. Hydrated moleculessuch as hygroscopic salts or other water containing molecules canprovide a source of ions prior to or during desorbtion. Finally,chemical additives such as surfactants and detergents can change the wayanalyte molecules and contaminates interact with each other and theimmobilization layer surface. This can be useful in cleaning the surfaceduring sample application, preventing agglomeration of analyte andpreventing strong adherence of the analyte to the immobilization layer.

[0061] These chemical additives can be introduced into the process inthe analyte preparation step, pre-coated on the immobilization layer,chemically attached to the immobilization layer, or introduced duringdesorption-ionization via fluidic or gaseous transport.

[0062] Mixed Phase Films

[0063] Matrix free desorption ionization mass spectrometry can also bemediated by mixed phase or composite material surfaces. In particular,when the desorbing/ionizing layer material is available in lessexpensive powder form, a cost effective approach is to form layers ofthis material from powder such that the particles are fixed in/by aresin material. The second (“glue”) material may serve more than justfixing the particles together, it may also function as the radiationabsorber and/or ionization enhancer. It is possible that the particlesand the “glue” material may have completely distinct roles essential todesorption/ionization. For instance, the particle material may be astrong absorber while a poor ionization enhancer. In contrast, thesecond material may be a poor absorber but be or contain effectiveionization enhancer(s). On the other hand, the superior properties ofthe two materials (radiation absorption and ionization enhancement) canbe brought together in a composite by mixing them. In this way asuperior desorbing/ionizing layer can be obtained. The composite layercould be comprised of more than two materials (either in particulate orglue form) to better tailor its superior desorbing/ionizing properties.A low cost method of making a composite film is mixing its components ina liquid solvent, and then placing the liquid mixture onto a substrate(e.g., casting, spinning, spray, brush, dipping, printing etc.techniques).

[0064] As a specific example, amorphous carbon—halogenated acidicpolymer composite films were prepared by spin casting. The carbon blackproduced from acetylene with an average particle size of 0.042 μm. TheHalogenated acidic polymer solution with 5.0-5.4% polymer content byweight was purchased from DuPont. Carbon black was mixed into theHalogenated acidic polymer solution to an equal amount of polymer byweight. The mixture was ultrasonicated for 6 h and stirred for 12 hbefore spun on 1″×1″ Corning 1737 glass substrates. A uniform filmthickness of 1.8 μm was obtained at a spin rate of 2000 rpm in 40 s. Thespin on was followed by a 120° C. thermal anneal for 15 minutes. Theresultant film was found to be a very efficient light absorber in thevisible and UV range as seen from its exceptionally low reflectance andtransmission characteristics in FIG. 6. This is simply attributed toamorphous carbon's being a very efficient light absorber. On the otherhand, the role of Halogenated acidic polymer other than being a resincould be ionization enhancement. This is because Halogenated acidicpolymer, a perfluorosulfonic acid/tetrafluoroethylene copolymer in theacid (H⁺) form, is well known for its being an efficient proton storage,transport and exchange properties. The conductivity of the film wasmeasured to be about 1.6 S/cm using glass substrates with coplanar metalcontacts. FIG. 2 depicts a desorption ionization mass spectrum takenfrom the surface of the Carbon black—Halogenated acidic polymer filmafter a 1.0 ng reserpine was dried from a droplet on the surface. It isevident from FIG. 7 that a very clear analyte signal is obtainable.

[0065] Integration with Preparation and Application Devices.

[0066] The deposited devices and mass analysis technique of thisinvention have the unique ability to be integrated with a large numberof sample delivery and preparation techniques plus a large number ofmass analyzers. Preparation of the analyte molecules can be as simple asplacing a drop of the molecules on the immobilization layer surface andallowing them to dry. It is also possible to allow the analyte moleculesto adsorb to the immobilization layer surface out of a gaseous or liquidsolution. This simple fluid handling can be performed by a number ofautomated, high throughput handling systems. More complex schemesinclude the use of micro-fluidic, on chip, system that performchromatography or purification. The deposited systems of this inventioncan be easily used in tandem with a chip-based system or integrated intothe micro-fluidic device. The use of an integrated micro-fluidic systemcan also be used to deliver desorption-ionization enhancing agents tothe analyte during mass analysis in order to prolong detection signal.

[0067] Many mass spectrometry techniques can be used to analyze thedesorbed-ionized species. These may include but are not limited to: timeof flight, quadrapole, ion trap, plasmon resonance or combinationsthereof.

[0068] The present invention comprises a class of morphology-tailoredstructures (or material systems) for the mass analysis and a method ofanalysis of atoms, molecules and molecular compounds and complexstructures such as adhered cells when coupled with lightdesorption-ionization mass spectrometry. These material systems act tohold analytes and allow them to desorb and ionize in the presence oflight without the traditional organic or non-organic matrix. A schematicof the difference between traditional MALDI and the technique of thisinvention is given in FIG. 1. The material systems of this invention arecomposed of one or more layers and a substrate to which they areadhered. The critical roles of adsorption, analyte immobilization,optical coupling, and substrate may be played by one or more materiallayers. one or more of these layers may be biased during photon exposureto influence desorption. The specifics of layer function and formationare detailed below.

[0069] Absorption Layer.

[0070] A necessary role that one or more layers, which may include thesubstrate, must play is the absorption of incident photons from thelight source. The light source may range from IR to UV wavelengths andfrom coherent and in phase (laser) to non-coherent. The choices of lightsource and absorber material are dependent on each other. The absorbermust be able to absorb enough of the incident light to providesufficient thermal energy to desorb the analytes from the immobilizationlayer, which may or may not be the absorber layer itself. The high lightadsorption coefficients of semiconductor materials make the use lowcost, light emitting diodes as a light source an attractive option, whencompared to the traditional UV laser sources that are necessary forMALDI. A specific embodiment of this invention is the use of a 337 nm UVlight source and Si or Ge based absorber materials. These two materials,in amorphous through crystalline phases, absorb UV light veryefficiently, and we have demonstrated this in FIGS. 2 and 3. This ideacan easily be extrapolated to include all semiconductors in the binary,tertiary, mixed, and graded varieties. All other materials for use as anabsorber, with appropriate optical properties are encompassed by thescope of this invention including: metals, semiconductors, insulators,ceramics, polymers, organic materials or composites thereof.

[0071] The only requirement of the position of the absorber layer in thematerial system of this invention is that the incident photons haveaccess to this layer. A unique aspect of this invention is the abilityto illuminate the device from any direction including through thesubstrate (rear of the device) and through the immobilization layer(front of the device). This is important if the analytes adsorb thelight wavelengths used for desorption and ionization. For instance smallmolecules, peptides and proteins adsorb UV wavelengths efficiently,which can lead to thermal degradation and fragmentation of the analyte,reducing the sensitivity of detection. Unlike MALDI, in our system theanalyte is not required to sit in the photon path, thus entirelyavoiding any photon/analyte interactions.

[0072] Immobilization Layer.

[0073] One or more layers in the material system of this invention mustcome into contact with the sample atoms/and or molecules. This layermust hold the sample and allow it to effectively desorb and ionize inthe presence of the energy generated by light adsorption in absorberlayer, which may also act the immobilization layer. The materialproperties required of the immobilization layer range widely and dependhighly on its interaction with the sample species. Also, if theimmobilization layer is in the light path between the light source andthe absorber layer, it must have optical properties such that incidentphotons are allowed to reach the absorber. Specific materials of thisinvention used for the immobilization layer include but are not limitedto silicon, germanium, silicon dioxide, germanium oxide, and theiralloyed forms. All other materials for use as an immobilization layer,with appropriate material properties are encompassed by the scope ofthis invention including: metals, semiconductors, insulators, ceramics,polymers, organic materials or composites thereof.

[0074] A. Morphology of the Immoblization Layer

[0075] The morphology and physical structure of this layer can betailored for specific applications. Three morphological structures ofthe immobilization layer, specific to this invention, include nanometerrange texturing, micrometer range texturing, and a macro-scale flatsurface. The first two types of films we categorize as discontinuousfilms. The macro-scale film is what we term a continuous film. Theadvantages and disadvantages of these three film structures are given inTable 1. The immobilization layer may be comprised of one or more ofthese morphological features. TABLE 1 Morphological structures of theimmobilization layer of this invention and their advantages anddisadvantages Morph- Possible ology Properties Advantages DisadvantagesExamples Nano- Ultra high Very high High Nanoscale meter surface loadingadsorption of deposited scale area capacity of ambient column/voidtexture High steric analyte noise network interaction High material withadsorption of molecular analyte species species from Strong wet or drycapillary ambient forces Excellent uniformity of analyte coverageMicro- - High High loading glancing meter surface capacity of anglescale area analyte deposited texture films Low adsorption of ambientnoise Flat Low surface Very low Poor Evaporated, surface area adsorptionof uniformity of spun-on, or ambient analyte sputtered noise coveragematerials Low sample loading density

[0076] B. Chemical Modifications and Additives to the ImmobilizationLayer

[0077] The surface and bulk chemistry of this layer can also be tailoredduring layer processing or post layer processing for specificinteractions with the analyte molecules, desorption/ionization enhancingspecies, and the immobilization layer surface. For example, fordeposited layers the chemistry of the film can be modified by plasma,thermal or wet chemistries such as, but not limited to; RIE, CVD, PECVD,DVD, MOCVD, PVD and wet chemical modification. A specific embodiment ofthis invention is to use surface chemical modifications either during orafter film deposition to control hydrophobicity and hydrophylicity ofthe film, such as the incorporation of carbon and fluorine whiledepositing a film or the growth of a thermal oxide. The chemistry of theimmobilization layer can be tailored for certain molecules to improvetheir desorption and ionization efficiency. Other functional groups canalso be used to tailor the interaction of the surface with the analytemolecules by altering hydrogen bonding, surface charge, van Der Wallsinteraction, polar and non-polar interactions, steric interaction,antigen/antibody reactions etc. The surface chemistry and energy canplay a critical role in the manner an analyte interacts with the surfaceduring adsorbtion. The manner in which a analyte crystallizes can play alarge role in the efficiency with which it desorbs and ionizes. As anexample, composite halogenated, acidic polymers provide an excellentsurface for analyte crystallization, while the acidic groups provide asource of ions for the ionization process. Crosslinked polymers are amore thermally stable surface that provides spectrums with very littlenoise from polymeric breakdown. Carbon black/halogenated polymercomposites possess an extremely hydrophobic surface composition, whencompared to the hydrophobicity of the polymer surface alone. The watercontact angle of these materials are in excess of 100 degrees.

[0078] Other chemical additives specifically enhance the ionization ofthe analyte molecules. The additives can be chemically bonded to thesurface prior to analyte application, applied to the surface in solidliquid or gas phase, or applied into the analyte solution prior orduring mass analysis. In order to improve ionization efficiency, anumber of materials, including but not limited to additives that aresalts, hydrated molecules, surfactants, detergents, chelators, acids andbases, may be added on the surface of the apparatus and dried prior tothe addition of the analyte, or added to the analyte prior to or duringcontacting the analyte to the apparatus. A specific chemicalmodification for improving ionization efficiency is the control ofsurface pH to enhance either negative or positive ion spectra. Forexample this can be accomplished simply by allowing HCl orTrifluoroacetic acid (TFA) to dry on the immobilization layer prior toapplying the analyte or attaching and acid or basic group to theimmobilization layer surface using a silanization reaction. Hydratedsalts such as MgCl₂ can provide a signifigant source of protons in acrystallized analyte for ionization. Chelating agents such as ammoniumcitrate remove salt ions which form adducts during mass analysis andalso disperse analytes for more uniform spatial distribution. Othersmall molecules added to the analyte, such as amino acids interact withthe analyte in the desorption plume and adsorb energy from the analytereducing fragmentation during mass analysis. HCl and TFA may also beadded to the analyte.

[0079] Another useful chemical modification can act to self-clean thedevice during sample application. By using a layer composition or thinsurface coating that is soluble in the sample solvent, the coating willbe dissolved, “cleaning” the surface of adhered contaminates such ashydrocarbons. A specific embodiment of this invention is the use of awater-soluble germanium oxide for its self-cleaning properties. Such anoxide will be inherently present as soon as Ge is exposed to atmosphere.This nascent oxide may be augmented by oxide formed in situ by wetchemistry, thermal or plasma oxidation or deposited as a thin film bythe deposition methods previously mentioned.

[0080] Optical Coupling Layer.

[0081] Another task that may be performed by one or more layers of thematerial system of this invention is coupling the incidentelectromagnetic radiation more effectively into the absorption layer.Several techniques can be used, such as those used modern solar celldevices, including but not limited to, optical impedance matching,anti-reflection coating, increasing the optical path length, andcombinations thereof. Specific techniques demonstrated in FIGS. 2 and 4include using silicon dioxide for an anti reflection coating and toserve as an immobilization layer, and using nano-structured silicon toact as an optical impedance matching medium as well as an absorber.Materials that can be used for this layer, with appropriate properties,include metals, semiconductors, insulators, ceramics, polymers, organicmaterials, or composites thereof.

[0082] Substrate.

[0083] For the material system of this invention, the substrate to whichthe layers are adhered onto may play one or more of the roles mentionedabove or simply serve as a support media. The only necessaryqualification of the substrate is that it must be compatible withsubsequent processing. The substrate may also be pre-patterned forsample preparation and localization. Specific embodiments demonstratedin this invention use inexpensive acrylic, and polyimide plastics,glasses and metal foils as substrates. In general, materials that can beused for this layer include metals, semiconductors, insulators,ceramics, polymers, organic materials, or composites thereof.

[0084] Deposition Methods.

[0085] Deposited films were preferably used to demonstrate thisinvention. Such deposited films can be deposited by a variety of methodsincluding but not limited to the following: PVD such as sputtering andevaporation, CVD, PECVD, ECR-PECVD, PEPVD, electroplating, sol-gel, tapecasting, self-assembly, liquid deposition, nebulization deposition, andspin coating. Specific techniques of the present invention includeevaporation, sputtering, PECVD, and combinations thereof. Films orlayers of the present invention are not limited to deposited films.

[0086] It is understood that certain films, i.e., polymer compositefilms, that are suitable for matrix-free photon desorption mass analysisdevices of the present invention are not required to be deposited. Forexample, micro-composite or nano-composite polymers films presentedherein may be used. They can be prepared by processing methods known inthe art such as mixing organic polymer(s) and inorganic materials(s) ina solvent, and thereafter forming a composite film from the mixture.Such composite films may be prepared, for example, by molding, casting,spin casting, spraying, and any combinations thereof, or otherprocedures known to produce such polymer composites.

[0087] Device Texturing and Patterning.

[0088] The texturing of one or more layers in the device of thisinvention can have several effects. Texturing of a reflective layerbehind the absorber (on the opposite side of the device from the lightsource), increases the optical path length and enhances opticalabsorption in thin absorber layers. Texturing of the immobilizationlayer can have various effects depending on the length scale considered.As shown in Table 1 above, micro-scale roughness allows more analyte anddesorption-ionization enhancing agents to be present per incident laserarea. This can increase the sensitivity and longevity of analyte signal.On the nano-scale, the surface roughness will not only enhance signalsensitivity and longevity, but may also act to enhance light couplinginto the absorber by impedance matching. The nanoscale texturing alsoallows effective adsorption of analytes from the gas or liquid phase andprovides better uniformity of the analyte distribution for morereproducible signal than achieved using other morphologies. Texturingcan be done by a variety of manufacturing techniques includingpre-fabricated or molded substrates, physical roughening, laserablation, lithographic processes, and textured film growth. Methods oftextured film growth of this invention include nano-structured PE-CVDgrowth conditions, zone growth model surface texturing, and glancingangle deposition.

[0089] Patterning of one or more of the layers in the device can servemany purposes. The localization of analytes, which is important forautomation and sample delivery purposes, can be done on a macroscopic ormicroscopic scale with wells either pre-formed on the substrate orproduced during subsequent film growth and processing. For instancewells could be hot embossed into a plastic substrate. Localization couldalso be attained by the plasma deposition of polymers or by theselective removal of an oxide layer. It could be attained by using“soft” lithographic patterning, such as PDMS stamping of molecules.Furthermore, patterning of the immobilization layer to causesdifferences in hydrophobicity, chemical affinity, acidity, charge andpolarity can localize and preferentially bind desired analytes.Patterning of a metallic grid on the immobilization layer can removecharge buildup during the desorbtion/ionization process in machinesrequiring a grounded stage. Finally, with the integration of thesedevices into micro-fluidic systems, patterning can be used to place thedevices where needed. Patterning can also be done by a variety ofmanufacturing techniques including pre-fabricated or molded substrates,physical scribing, stamping, embossing, laser ablation and lithographicprocesses.

[0090] Integration with Preparation, Application, and Analysis Devices.

[0091] The deposited devices and mass analysis technique of thisinvention have the unique ability to be integrated with a large numberof sample delivery and preparation techniques plus a large number ofmass analyzers. Preparation of the analyte can be as simple as placing adrop of the molecules on the immobilization layer surface and allowingit to dry. It is also possible to allow the analyte to adsorb to theimmobilization layer surface out of a gaseous or liquid solution. Thissimple gas or fluid handling can be performed by a number of automated,high throughput sampling systems. More complex schemes include the useof computer integrated micro-fluidic, on chip, systems that performchromatography or purification. The deposited systems of this inventioncan be easily used in tandem with a chip-based system or integrated intothe micro-fluidic device. The use of an integrated micro-fluidic systemcan also be used to deliver desorption-ionization enhancing agents, suchas water, to the analyte during mass analysis in order to prolongdetection signal.

[0092] Many mass spectroscopic methods can be used to analyze thedesorbed-ionized species. These may include but are not limited to: timeof flight, quadrapole, ion trap, plasmon resonance or combinationsthereof.

[0093] Device Structure and Layer Organization.

[0094] The layer options and requirements detailed above enable themorphology-tailored material structures of this invention to be uniquelydesigned for optimal performance based on the analytes, their samplepreparation, the type of electromagnetic source used fordesorption-ionization, the mass analysis technique used and integrationtechniques employed. However, there are basic rules that apply to theoverall device structure. First, the impinging photons must be able toenter the absorber layer or layers of the device. Second, theimmobilization layer must enable the desorbed analytes to enter thenecessary mass detection area. FIG. 5 provides a variety of specificdevice structures unique to this invention.

[0095] Although the present invention describes in detail certainembodiments, it is understood that variations and modifications existknown to those skilled in the art that are within the invention.Accordingly, the present invention is intended to encompass all suchalternatives, modifications and variations that are within the scope ofthe invention as set forth in the following claims.

What is claimed is:
 1. An apparatus for providing an ionized analyte formass analysis by photon desorption comprising: at least one layer forcontacting an analyte; and a substrate on which said layer is deposited,wherein said analyte upon irradiation of said apparatus with a photonsource desorbs and ionizes for mass analysis.
 2. The apparatus of claim1, further comprising one or more layers deposited on said substratethat act to absorb and convert photons to energy sufficient to desorband ionize said analyte.
 3. The apparatus of claim 1, wherein saidsubstrate upon irradiation absorbs and converts photon energy to energysufficient to desorb and ionize said analyte.
 4. The apparatus of claim1, wherein said substrate is selected from the group consisting ofsemiconductors, glasses, plastics, polymers, metals, ceramics,insulators, organic materials, inorganic materials, or any combinationsthereof.
 5. The apparatus of claim 2, wherein said one or more layers isselected form the group consisting of metals, semiconductors,insulators, ceramics, polymers, organic materials, inorganic materials,and any combinations thereof.
 6. The apparatus of claim 4, wherein saiddeposited layer enhances the absorption of photons by optical impedancematching, by acting as an anti-reflective coating, by increasing thephoton path length, or any combinations thereof.
 7. The apparatus ofclaim 1, wherein said deposited layer contacting said analyte isselected from the group consisting of silicon, silicon dioxide,germanium, germanium oxide, indium, gallium, cadmium, selenium,tellurium, and alloys and compounds thereof, carbon, hydrogen,semiconductors, insulators, metals, ceramics, polymers, other inorganicmaterial, organic material, or any combinations thereof.
 8. Theapparatus of claim 1, wherein said layer is deposited by physical vapordeposition, chemical vapor deposition, liquid deposition, molecular beamepitaxy, plasma assisted chemical vapor deposition, sol-gels,nebulization, spraying, electroplating, tape casting, spin coating,assembly from liquid chemical precursors, printing, self-assembly andany combinations thereof.
 9. The apparatus of claim 2, wherein saidlayer is deposited by physical vapor deposition, chemical vapordeposition, liquid deposition, molecular beam epitaxy, plasma assistedchemical vapor deposition, sol-gels, nebulization, spraying,electroplating, tape casting, spin coating, assembly from liquidchemical precursors, printing, self-assembly and any combinationsthereof.
 10. The apparatus of claim 1, wherein said deposited layer is acontinuous film, a discontinuous film or any combinations thereof. 11.The apparatus of claim 1, wherein said layer contacting said analyte isphysically or chemically modified, surface functionalized, or patterned.12. The apparatus of claim 11, wherein the surface of said layer ischemically modified to control acid behavior, basic behavior,hydrophobicity, hydrophylicity, and any combinations thereof.
 13. Theapparatus of claim 1, wherein the thickness of said layer is essentiallyuniform from 5 nm to 10 microns.
 14. The apparatus of claim 1, whereinsaid layer contacting an analyte is non-textured, micro-scale textured,nano-scale textured, or any combinations thereof.
 15. The apparatus ofclaim 1, wherein the analyte is in an amount greater than 1 attomole.16. The apparatus of claim 1, further comprising a micro-fluidicapparatus, a nano-fluidic apparatus, or combination thereof.
 17. Theapparatus of claim 1, further comprising a mass spectrometer foranalysis of the mass of said analyte.
 18. The apparatus of claim 17,wherein said mass analysis is by time of flight mass spectrometer,quadrapole mass spectrometer, ion trap device, or any combinationsthereof.
 19. The apparatus of claim 2, wherein one or more of saiddeposited layers is a continuous film, a discontinuous film, or anycombinations thereof.
 20. The apparatus of claim 1, wherein one or moreof said contacting layers is physically or chemically modified, surfacefunctionalized, or patterned.
 21. The apparatus of claim 20, wherein thesurface of said layer is chemically modified to control acid behavior,basic behavior, water content, hydrophobicity or hydrophylicity, and anycombinations thereof.
 22. The apparatus of claim 2, wherein thethickness of said layer is essentially uniform from 5 nm to 10 microns.23. The apparatus of claim 1, wherein said layer contacting an analyteis non-textured, micro-scale textured, nano-scale textured, or anycombinations thereof.
 24. The apparatus of claim 1, wherein the analyteis in an amount less than 1 attomole.
 25. The apparatus of claim 1,further comprising a micro-fluidic apparatus, a nano-fluidic apparatus,or combination thereof.
 26. The apparatus of claim 1, further comprisinga device for analysis of the mass of said analyte.
 27. The apparatus ofclaim 26, wherein said device is a time of flight mass spectrometer, aquadrapole mass spectrometer, an ion trap device, or any combinationsthereof.
 28. A method for providing an ionized analyte for analysis ofmass comprising: providing an apparatus comprising at least one layerfor contacting an analyte wherein said layer is deposited on asubstrate; contacting an amount of an analyte containing entities suchas molecules whose mass or masses are to be determined with saiddeposited layer; and irradiating said apparatus to desorb and ionizesaid analyte.
 29. The method of claim 28, wherein said analyte issubstantially free of a matrix.
 30. The method of claim 28, wherein saidanalyte is selected from the group comprising organic chemicalcompositions, inorganic chemical compositions, biochemical compositions,cells, micro-organisms, peptides, polypeptides, proteins, lipids,carbohydrates, drug candidate molecules, drug molecules, drugmetabolites, combinatorial chemistry products, nucleic acids, and anycombinations thereof.
 31. The method of claim 28, wherein said apparatusfurther comprises on or more layers deposited on said substrate thatupon irradiating said apparatus absorb and convert photon energysufficient to desorb and ionize said analyte.
 32. The method of claim28, wherein said substrate upon irradiation of said apparatus absorbsand converts photons to energy sufficient to desorb and ionize saidanalyte.
 33. The method of claim 28, wherein said substrate is selectedfrom the group consisting of semiconductors, glasses, plastics,polymers, metals, ceramics, insulators, organic materials, inorganicmaterials, and any combinations thereof.
 34. The method of claim 31,wherein said one or more deposited layers enhance the absorption oflight by optical impedance matching, by acting as an anti-reflectioncoating, by increasing the photon path length, or by any combinationsthereof.
 35. The method of claim 31, wherein said one or more layers isselected form the group consisting of metals, semiconductors,insulators, ceramics, polymers, organic materials, inorganic materials,and any combinations thereof.
 36. The method of claim 28, wherein saiddeposited layer contacting said analyte is selected form the groupconsisting of silicon, silicon dioxide, germanium, germanium oxide,indium, gallium, cadmium, selenium, tellurium, and alloys and compoundsthereof, carbon, hydrogen, semiconductors, insulators, metals, ceramics,polymers, other inorganic material, organic material, or anycombinations thereof.
 37. The method of claim 28, wherein said depositedlayer of said apparatus is deposited by physical vapor deposition,chemical vapor deposition, liquid deposition, molecular beam epitaxy,plasma assisted chemical vapor deposition, sol-gels, nebulization,electroplating, tape casting, spin coating, assembly from liquidchemical precursors, printing, self-assembly, and any combinationsthereof.
 38. The method of claim 31, wherein said one or more layers isdeposited by physical vapor deposition, chemical vapor deposition,liquid deposition, molecular beam epitaxy, plasma assisted chemicalvapor deposition, sol-gels, nebulization, electroplating, tape casting,spin coating, assembly from liquid chemical precursors, printing,self-assembly, and any combinations thereof.
 39. The method of claim 28,wherein said deposited layer of said apparatus contacting said analyteis a continuous film, a discontinuous film, or any combinations thereof.40. The method of claim 28, wherein said deposited layer of saidapparatus contacting said analyte is physically or chemically modified,surface functionalized, patterned, or any combinations thereof.
 41. Themethod of claim 40, wherein said layer is chemically modified to controlhydrophobicity or hydropilicity.
 42. The method of claim 40, whereinsaid layer is chemically modified to control the surface pH of saidlayer.
 43. The method of claim 28, wherein said layer contacting saidanalyte is non-textured, micro-scale textured, nano-scale textured, orany combinations thereof.
 44. The method of claim 43, wherein said layeris textured by prefabricating textured substrates, physical roughening,laser ablation, lithographic processes, textured film growth,self-assembly deposition, or any combinations thereof.
 45. The method ofclaim 28, wherein said analyte is in an amount less than 1 attomole. 46.The method of claim 28, wherein the thickness of said layer isessentially uniform from 5 nm to 10 microns.
 47. The method of claim 28,further comprising adding an enhancing agent to said analyte prior toirradiating said apparatus.
 48. The method of claim 47, wherein saidenhancing agent is ammonium citrate, HCl, TFA, salts, hydratedmolecules, surfactants, detergents, acids, bases, and any combinationsthereof.
 49. The method of claim 28, wherein said apparatus furthercomprises a micro-fluidic apparatus, a nano-fluidic apparatus, orcombination thereof.
 50. The method of claim 28, further comprisinganalyzing the mass of said ionized analyte by a device.
 51. The methodof claim 50, wherein said analyzing the mass of said ionized analyte isby time of flight mass spectroscopy, quadrapole mass spectroscopy, iontrap device, or any combinations thereof.
 52. A method for determining aphysical property of an analyte component comprising: providing anapparatus comprising at least one layer for contacting an analyte and asubstrate on which said layer is deposited; positioning an amount of ananalyte on the layer used for contacting an analyte of said apparatus;irradiating said apparatus having said contacted analyte; desorbing andionizing at least one component of said analyte; and analylzing saidionized at least one analyte component for a physical property.
 53. Themethod of claim 52, wherein said physical property of said at least oneanalyte component is the mass to charge ratio (m/z) of the ionizedanalyte.
 54. The method of claim 53, wherein said physical property isanalyzed by mass spectrometry.
 55. The method of claim 54, wherein saidmass spectroscopy is time of flight, quadrapole, ion trap, or anycombinations thereof.
 56. The method of claim 52, wherein said analyteis substantially free of photon-absorbing matrix.
 57. The method ofclaim 52, wherein said analyte is selected from the group consisting oforganic chemical compositions, inorganic chemical compositions,biochemical compositions, cells, micro-organisms, peptides,polypeptides, proteins, lipids, carbohydrates, drug candidate molecules,drug molecules, drug metabolites, combinatorial chemistry products,nucleic acids, and any combinations thereof.
 58. The method of claim 52,wherein said apparatus further comprises one or more layers deposited onsaid substrate that upon irradiating said apparatus absorb and convertphotons to energy sufficient to desorb and ionize said analyte.
 59. Themethod of claim 58, wherein said one or more layers is selected from thegroup consisting of metals, semiconductors, insulators, ceramics,polymers, organic materials, inorganic materials, and any combinationsthereof.
 60. The method of claim 58, wherein said one or more depositedlayers enhances the absorption of light by photons impedance matching,by acting as an anti-reflection coating, by increasing the optical pathlength, or by any combinations thereof.
 61. The method of claim 52,wherein said substrate upon irradiation of said apparatus absorbs andconverts photons to energy sufficient to desorb and ionize said analyte.62. The method of claim 52, wherein said substrate is selected from thegroup consisting of semiconductors, glasses, plastics, polymers, metals,ceramics, insulators, organic materials, inorganic materials, and anycombinations thereof.
 63. The method of claim 52, wherein said depositedlayer contacting said analyte is selected form the group consisting ofsilicon, silicon dioxide, germanium, germanium oxide, indium, gallium,cadmium, selenium, tellurium and alloys and compounds thereof, carbon,hydrogen, semiconductors, insulators, ceramics, metals, polymers, otherinorganic material, organic material, and any combinations thereof. 64.The method of claim 52, wherein said layer is deposited by physicalvapor deposition, chemical vapor deposition, liquid deposition,molecular beam epitaxy, plasma assisted chemical vapor deposition,sol-gels, nebulization, electroplating, tape casting, spin coating,assembly from liquid chemical precursors, printing, self-assembly, andany combinations thereof.
 65. The method of claim 58, wherein said layeris deposited by physical vapor deposition, chemical vapor deposition,liquid deposition, molecular beam epitaxy, plasma assisted chemicalvapor deposition, sol-gels, nebulization, electroplating, tape casting,spin coating, assembly from liquid chemical precursors, printing,self-assembly, and any combinations thereof.
 66. The method of claim 52,wherein said deposited layer of said apparatus contacting said analyteis a continuous film, a discontinuous film, or any combinations thereof.67. The method of claim 52, wherein said deposited layer of saidapparatus contacting said analyte is physically or chemically modified,surface functionalized, patterned, or any combinations thereof.
 68. Themethod of claim 67, wherein said layer is chemically modified to controlhydrophobicity or hydrophilicity.
 69. The method of claim 67, whereinsaid layer is chemically modified to control the surface pH of saidlayer.
 70. The method of claim 52, wherein said layer contacting saidanalyte is non-textured, micro-scale textured, nano-scale textured, orany combinations thereof.
 71. The method of claim 70, wherein said layeris textured by prefabricating textured substrates, physical roughening,laser ablation, lithographic processes, textured film growth, or anycombinations thereof.
 72. The method of claim 52, wherein said analyteis in an amount greater than 1 attomole.
 73. The method of claim 52,wherein the thickness of said deposited layer is essentially uniform.74. The method of claim 73, wherein said thickness of said depositedlayer is from 5 nm to 10 microns.
 75. The method of claim 52, furthercomprising adding an [ionizing] enhancing agent to said analyte prior toirradiating said apparatus.
 76. The method of claim 75, wherein saidenhancing agent is ammonium citrate, HCl, TFA, salts, hydratedmolecules, surfactants, chelating agents, detergents, acids, bases, andany combinations thereof.
 77. The method of claim 52, wherein saidapparatus further comprises a micro-fluidic apparatus, a nano-fluidicapparatus, or combinations thereof.
 78. The method of claim 52, furthercomprising analyzing the masses of said one or more components of saidionized analyte by a device.
 79. The method of claim 78, whereinanalyzing the mass is by time of flight mass spectroscopy, quadrapolemass spectroscopy, ion trap device, or any combinations thereof.
 80. Anapparatus for determining the masses of one or more components of ananalyte comprising a substrate, an analyte contacting the substrate, asource of radiation irradiating the substrate wherein illumination ofthe substrate causes the desorption and ionization of the analyte, asource of positive or negative voltage connected to the substrate thatcontrols and directs the ionized analyte, and a spectrometer thatanalyzes the mass to charge ratio (m/z) of the ionized analytecomponents wherein the improvement comprises: a substrate that is anapparatus comprising at least one layer for contacting an analytedeposited on a substrate material wherein said apparatus has opticalproperties to absorb and convert photons to energy sufficient to desorband ionize said analyte.
 81. An apparatus according to claim 80, whereinthe analyte is substantially free of photon absorbing matrix.
 82. Anapparatus according to claim 80, wherein one or more of said layers ofsaid apparatus is a continuous film, a discontinuous film, or anycombinations thereof.
 83. A method of improving the detection of ananalyte by laser desorption mass spectrometry comprising the steps of:providing a substrate having a fluorinated coated sample loading region;providing an analyte dissolved in a first liquid as a sample; andcontacting the coated sample loading region with the sample wherein thesample does not spread on the coated sample loading regions to form asample loaded substrate.
 84. A device of claim 1 where the depositedlayer is a composite material comprising an organic material and aphoton adsorbing micro or nanoparticle.
 85. A device of claim 84 wherethe organic material is polymer.
 86. A device of claim 85 where thepolymer is a halogenated material.
 87. A device of claim 86 where thepolymer is an acid.
 88. A device of claim 85 wherein the polymer is afluorinated/sulfur containing material.
 89. A device of claim 84 wherethe photon adsorbing micro or nanoparticle is a semiconductor.
 90. Adevice of claim 84 where the photon adsorbing micro or nanoparticle is ametal, organic, insulator or inorganic material.
 91. A device of claim84 where the photon adsorbing micro or nanoparticle is carbon.